System and method for providing universal additional functionality for power meters

ABSTRACT

A system and method for providing an additional option function to existing functionality of a meter device configured for measuring parameters of energy is provided. The meter device is coupled with an option device for exchanging data between the meter and the option devices along at least one data path, including exchanging initialization data provided by the option device between the meter device and the option device, wherein the initialization data is useable by the meter device for configuring the meter device to be in condition to operate with the option device. The data exchanged between the meter device and the option devices are processed by at least one processor. Upon the coupling of the devices and the exchanging of the initialization data, the meter device is operated with the option device for adding the option function to existing functionality of the meter device.

This application is a continuation application of U.S. application Ser.No. 12/345,007 filed Dec. 29, 2008, now U.S. Pat. No. 7,953,565, whichis a continuation application of U.S. application Ser. No. 11/701,160,filed Feb. 1, 2007, now U.S. Pat. No. 7,477,998, which is a continuationapplication of an application filed on Mar. 28, 2005, assigned U.S.application Ser. No. 11/091,254, entitled “System and Method forProviding Universal Additional Functionality for Power Meters”, now U.S.Pat. No. 7,184,904, and which claims priority under 35 U.S.C. section119 to U.S. Provisional Application Ser. No. 60/645,439 filed on Jan.20, 2005, and entitled “Universal Option Slot For A Power Meter”, theentire contents of all applications are expressly incorporated herein intheir entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This disclosure relates to meters for measuring parameters of electricalenergy. In particular, this disclosure relates to a system and methodfor providing universal additional functionality for energy meters.

2. Description of the Related Art

Electrical utility companies (“utilities”) track electric usage bycustomers by using power meters. These meters track the amount of powerconsumed at a particular location, such as a substation. The electricutility companies may use the power meter to charge its customers fortheir power consumption, i.e., revenue metering.

Traditionally, power meters used mechanical means to track the amount ofconsumed power. The inductive spinning disk power meter is stillcommonly used. The spinning disk drives mechanical counters that trackthe power consumption information. A display device, such as a dial, isprovided for displaying the measurements read, which can then bemanually recorded as desired by an operator.

Newer to the market are electronic power meters. Electronic meters havereplaced the older mechanical meters, and utilize digital sampling ofthe voltage and current waveforms to generate power consumptioninformation. A display device, such as an LED for displaying digitaldata, is provided for displaying the measurements read. In manyinstances it is desirable to further process or utilize themeasurements. It has been customary to provide a power meter withselected capabilities or options, such as for further processing themeasurements, transmitting the measurements via a desired communicationmedium, or controlling other devices in accordance with themeasurements. Typically, a customized meter is provided having optionsselected in accordance with the intended application that the meter isused in. From a manufacturing point of view, customization of individualmeters is costly. Furthermore, upgrading the meter to include additionaloptions is typically performed at the field by an expert and requirescustomized programming of the upgraded meter. Experience has shown thatoperators of the meter rely heavily on technical support for learninghow to use the meter's options and for troubleshooting problems, all ofwhich is costly to the manufacturer. The additional costs are mostlikely passed on to the customer.

Therefore, it is an aspect of the disclosure to provide a power meterwhich may be used with a variety of options, where the options areexchangeable or replaceable with simple and minimal actions by anoperator of the meter.

It is further an aspect of the disclosure to provide a variety ofoptions in which the respective options are packaged for simpleinstallation with a meter by an operator of the meter.

SUMMARY

In accordance with the present disclosure, an option device is providedfor coupling with a meter device that is configured for measuringparameters of energy. The option device includes at least one componentfor providing an option function and at least one nonvolatile storagedevice for storing initialization data useable by the meter device forconfiguring at least one of the meter device and the option device to bein condition to operate with the at least one of the meter device andthe option device. The option device further includes at least oneconnector for coupling with the meter device for exchanging data withthe meter device along at least one data path, the exchanged dataincluding the initialization data, and at least one processor for atleast one of processing data exchanged between the meter and the optiondevices and communicating with the at least one component. The optiondevice further includes isolator circuitry which is provided along apath between the at least one processor and a connector of the at leastone connector of the meter device for electrically isolating the optiondevice from the meter device. Upon coupling the at least one connectorwith the meter device, the meter device operates with the option devicefor adding the option function to existing functionality of the meterdevice. The meter device is of the type configured for measuringparameters of energy.

In accordance with another embodiment of the disclosure, the at leastone connector of the option device includes a first connector forcoupling the at least one nonvolatile storage device with the meterdevice for exchanging the initialization data between the at least onenonvolatile storage device and the meter device, and a second connectorfor coupling the at least one processor and the meter device forexchanging data there between.

In accordance with yet another embodiment of the disclosure, a method isprovided for providing an additional option function to existingfunctionality of a meter device configured for measuring parameters ofenergy. The method includes the steps of selecting an option device froma plurality of option devices; coupling the meter device of the typeconfigured for measuring parameters of energy with the selected optiondevice and exchanging data between the meter and the selected optiondevices along at least one data path including exchanging initializationdata provided by the selected option device between the meter device andthe selected option device. The initialization data is useable by themeter device for configuring at least one of the meter device and theselected option device to be in condition to operate with the at leastone of the meter device and the selected option device. The methodfurther includes the steps of processing the data exchanged between themeter and the selected option devices, and operating the meter devicewith the selected option device for adding the option function toexisting functionality of the meter device upon exchanginginitialization data and coupling the meter device with the selectedoption device. In accordance with still another embodiment of thedisclosure, the method includes electrically isolating the meter devicefrom the selected option device along at least one data path of the atleast one data path.

In accordance with still another embodiment of the disclosure, a meterdevice configured for measuring at least one parameter of energy isprovided. The meter device includes at least one input line forreceiving energy for measuring at least one parameter thereof, andcircuitry for processing the received energy. At least one connector isprovided and configured for interchangeably coupling the meter devicewith a plurality of option devices, including an option device providingan option function for exchanging data therebetween, the exchanged dataincluding initialization data provide by the option device. At least oneprocessor is provided for using the initialization data for configuringat least one of the meter device and the option device to be incondition to operate with the other of the meter device and the optiondevice. Upon coupling the respective option device to the at least oneconnector, the at least one of the meter device and the option device isconfigured in accordance with the initialization data and the meterdevice is operated with the option device for adding the option functionto existing functionality of the meter device.

In accordance with a further embodiment of the disclosure, the at leastone connector of the meter device includes a first connector forcoupling with the option device for providing for transmission ofinitialization data provided by at least one storage device of theoption device to the meter device and a second connector for couplingwith the option device for providing for exchanging of data between atleast one processor of the option device and the meter device. The meterdevice further includes isolator circuitry coupled to the secondconnector for electrically isolating the meter device from the at leastone processor of the option device.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the disclosure will be described herein belowwith reference to the figures wherein:

FIG. 1 is a front perspective view of a metering system for measuringenergy parameters having a meter device and at least one option devicefor installation within the meter device in accordance with the presentdisclosure;

FIG. 2 is a schematic diagram of the meter system shown in FIG. 1; and

FIG. 3 is a schematic diagram of an option device shown in FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to the drawings wherein like reference numerals identifysimilar structural elements, there is illustrated in FIG. 1 a meteringsystem 10 having a meter device 12 provided with at least one optioninterface 14 configured for receiving a respective option device 16. Arespective option device 16 may be installed with (e.g., coupled to) orremoved from a desired option interface 14, where the respective optioninterfaces 14 are preferably substantially identical in configuration,e.g., standardized. The respective option devices 16 are provided withan associated option function, where different option devices 16 havedifferent associated option functions. Installation of a respectiveoption device 16 provides the associated option function to the meterdevice 12, thus providing the meter device 12 with additionalfunctionality in addition to its existing functionality. Theinstallation and provision of the option function to the meter device 12is performed in a plug-n-play fashion. Configuration of the meter device12 and/or option device 16 for operating together is performedautomatically and in real-time upon plugging the option device 16 intothe meter device 12 without any further intervention, such as by anoperator. Furthermore, the option devices 16 may be swapped, e.g., afirst option device 16 may be removed from an option interface 14, and asecond option device 16 may installed in the same option interface 14for replacing the first option device 16.

The option interface 14 includes mechanical features (not shown) forreceiving and holding an inserted option device 16, such as a connectorsimilar to a printed circuit board (PCB) edge card connector. The optioninterface 14 may further include mechanical features (not shown) forejecting the option device 16 upon request. Ejection of an option device16 from an option interface 14 may be initiated, for example, byactuation of an ejection button 18 and/or by software control signals.The option device 16 may also be manually removed from the optioninterface 14.

The meter device 12 includes at least one input line 6 for receiving atleast one energy input (e.g., current, voltage or power). The meterdevice 12 reads one or more parameters of the input energy and generatescorresponding measured values. The meter device 12 may further generateadditional signals, such as control signals, which relate to the inputsto the meter device 12. The meter device 12 may be, for example, a panelmeter (e.g., for use with a switchboard) or a revenue meter (e.g., foruse at a substation or at the site of a user of the energy). The meterdevice 12 further includes a control panel 20, which may include atleast one display, and at least one user input device (e.g., a keypad,control switches and/or knobs).

With reference to FIG. 2, the meter device 12 includes circuitry 8 forprocessing the energy received at the input line 6. The circuitry 8 mayinclude, for example, step-down circuitry, at least one amplifyingdevice (e.g., an operational amplifier), a current transformer, sampleand hold circuitry, analog to digital converter circuitry, multiplexerdevice, filter circuitry, or a combination thereof for processing thereceived inputs and generating a corresponding measured value. The meterdevice 12 further includes a processor assembly 202 including at leastone processor (e.g., a digital signal processor (DSP)) and at least onestorage device (e.g., RAM, ROM, EPROM, flash memory, etc.) accessible bythe at least one processor. During operation of the meter device 12, theprocessor assembly 202 of the meter device 12 executes a series ofprogrammable instructions which may be stored in the at least onestorage device.

The meter device 12 is shown having first and second option interfaces14A and 14B, respectively, each having an option device 16 coupledthereto. The interfaces 14A and 14B are shown as slots which receive anoption device 16 and couple with the option device 16 when the optiondevice 16 is inserted in the slot. An exploded view is provided ofinterface 14A and the corresponding inserted option device 16 forshowing connecting elements between the interface 14A and correspondinginserted option device 16. The interfaces 14A and 14B are not limited tobeing configured as slots, and other types of interfaces may be used,which may include cables, physically mating connectors, and/or wirelessconnectors, etc.

The respective interfaces 14A,B of the meter device 12 include at leastone of a first connector 204 in communication with a first data path 206(e.g., data bus) and a second connector 208 in communication with asecond data path 210 (e.g., data bus). The option device 16 includes atleast one of a first connector 212 and a second connector 214, whereinthe first connector 212 mates with connector 204 of the interface 14,and the second connector 214 mates with connector 208 of the meterdevice 12.

The first and second data paths 206 and 210, respectively, communicatewith the processor assembly 202, where in the preferred embodiment thefirst data path 206 is serial and the second data path 210 is parallel,but is not limited thereto. It is contemplated that more than one firstdata path 206 and/or second data path 210 is provided, where respectiveoption devices 16 are coupled to different data paths of the more thanone first data path 206 and/or second data path 210. The data paths ofthe more than one first data path 206 may be joined or disjoint (e.g.,independent of one another). Likewise, data paths of the more than onesecond data path 210 may be joined or disjoint. It is furthercontemplated that data paths 206 and/or 210 are coupled to a device inthe meter device 12 other than the processor assembly 202.

With respect to FIG. 3, option device 16 is shown in greater detail. Theoption device 16 is packaged for easy installation with the meter device12, and preferably as an option device for insertion within a slot ofthe option interface 14. The option device 16 includes at least oneoption component 302 for performing an associated option functionprovided by the option device 16, and a processor 304 for communicatingwith the meter device 12 and with the option components 302 (e.g., forsharing data and/or providing control thereto). During operation of theoption device 16, the processor 304 of the option device 16 executes aseries of programmable instructions which may be stored in at least onestorage device accessible by the processor 304 and preferably integratedwith the processor 304. The processor assembly 202 and the processor 304preferably operate in a master/slave relationship.

The option device 16 further includes a non-volatile storage device 312,e.g., an EEPROM. Connector 212 of the option device 16 is coupled to thestorage device 312 and is exposed from a housing 313 of the optiondevice 16 for mating with connector 204 of the option interface 14. Whenthe option device 16 is coupled to the option interface 14 (e.g.,inserted into the corresponding slot) a data stream (preferably serial)is transmitted from the storage device 312, through the connector 212 ofthe option device 16 and to the connector 204 of the option interface14, and/or vice versa. In a preferred embodiment of the disclosure, whenthe option device 16 is coupled to the meter device 12 and a data pathis established from the storage device 312 to the meter device 12, thestorage device 312 begins to transmit the initialization datacontinually.

Data stored in the storage device 312 includes initialization data,which may include, for example, identification data identifying theoption device 16, calibration data and/or setup data which the meterdevice 12 may use for configuring itself to operate in conjunction withthe option device 16 for providing the associated option function of theoption device 16 as additional functionality to the meter device 12 inaddition to existing functionality of the meter device 12. Theinitialization data is sufficient for preparing the meter device 12 tooperate with the option device 16 for adding the additional optionfunction to the existing functionality of the meter device 12.Preferably, the storage device 312 is tested, calibrated and programmed(e.g., the initialization data is stored therein) by the manufacturer ofthe option device 16. Testing and calibrating the option device 16 mayinclude injecting a known energy (e.g., voltage or current) into thedevice and measuring the corresponding output energy and determining thecorresponding gain factor and/or offset factor, which are included inthe initialization data. It is contemplated that a user or themanufacturer may re-configure the option device 16 by re-programming it,such as by adding or changing information stored by the storage device312. For example, after prolonged use of the option device 16 the optiondevice 16 may need to be recalibrated and have updated initializationdata stored therein. The option device 16 may also be configurable by auser before installation in the meter device 12. User configuration ofthe option device 16 may include selection of a protocol, baud rate,clock setting, etc. The user configured settings are included in theinitialization data. The configuration settings are stored on the optiondevice 16 and are retained when the option device 16 is de-energized orremoved from the meter device 12.

The processor assembly 202 continually checks for the presence of theoption device 16, preferably by checking for receipt of data fromstorage device 312, such as by polling a flag, an address or a register.Accordingly, the processor assembly 202 recognizes when the optiondevice 16 has been coupled (e.g., installed with the meter device 12),replaced (e.g., removed from the meter device 12 and another optiondevice 16 coupled to the meter device 12), or removed from the meterdevice 12. The option devices 16 may be installed, replaced or removedbefore power-up of the meter device 12 and/or during usage of the meterdevice 12.

Upon detecting that an option device 16 has been installed or replaced,e.g., upon power-up of the meter device 12 or installation of an optiondevice 16, the processor assembly 202 uses the initialization data toconfigure the meter device 12 to operate with the option device 16,which may include transmitting data to the processor 304 for configuringthe option device 16 to operate with the meter device 12. Configurationof the meter device 12 also includes detecting if the configurationstate of the option device 16, including if the option device 16 hasbeen configured by a user, and to what degree. The meter device 12operates with the option device 16 in its configured state using theconfiguration data. Accordingly, upon installing or plugging the optiondevice 16 into the meter device 12, the meter device 12 recognizes theinstallation in real-time and automatically configures itself using theinitialization data to operate with the option device 16, includingadding the option function to the meter device's existing functionality,such as in a plug-n-play fashion.

The initialization data may include parameter values and/or programmableinstructions. A parameter value of the initialization data may be usedto calibrate the meter device 12 to operate compatibly with the optiondevice 16. The data identifying the option device 16 may be used forretrieving from a storage device accessible by the processor assembly202 one or more parameter values which correspond to the option device16. A parameter value may include, for example, a gain factor and anoffset factor for the option device 16, which the processor assembly 202will use during gain computations or will pass to the processor 304 touse during gain computations during operation of the meter device 12.

A parameter value or identification data may further be used by theprocessor assembly 202 to retrieve a selected set of executable softwareinstructions from a storage device accessible by the processor assembly202. Preferably, the storage device is incorporated into the meterdevice 12. The retrieved set of executable software instructions isexecuted by the processor assembly 202 for the meter device 12 tooperate with the option device 16 for adding the option function of theoption device 16 to the existing functionality of the meter device 12.Furthermore, programmable instructions included with the initializationdata may be executed by the processor assembly 202 for the meter device12 to operate with the option device 16 for adding the option functionof the option device 16 to the existing functionality of the meterdevice 12.

Additionally, the option device 16 may include an interface device 314for providing an interface between the processor 304 of the optiondevice 16 and the processor assembly 202 and/or other devices of themeter device 12 for allowing communication therebetween when the optiondevice 16 is coupled to the meter device 12. Connector 214 of the optiondevice 16 is coupled to the interface device 314 and exposed from thehousing 313 for mating with connector 208 of the interface 14.

In a preferred embodiment of the disclosure, the interface device 314includes at least one parallel/serial conversion device 316, such as aUniversal Asynchronous Receiver/Transmitter (UART) device, forconverting data having a serial format into data having a parallelformat, and vice versa. Accordingly, data exchanged via connector 214has a parallel format, where data transmitted along data path 320 has aserial format. The interface device 314 preferably further includesisolator circuitry 318 having a device such as an optical-electricalisolator, for electrically isolating data path 320 a from data path 320b, and the meter device 12 from the option device 16 for providingprotection to the isolated devices from ground loops, short circuits,noise, surges, etc.

Data transmitted in parallel format from the processor assembly 202and/or other devices of the meter device 12 which is received by theconversion device 316 is converted to serial format. The serial datapasses through the isolator circuitry 318 along data path 320 and to theprocessor 304. Likewise, data transmitted in serial format from theprocessor 304 along data path 320 passes through the isolator circuitry318, and then is received by the conversion device 316, which convertsthe data to parallel format and is provided to the processor assembly202 and/or other devices of the meter device 12 via connector 214,connector 208 and bus 210.

It is contemplated that the conversion device 316 and/or the isolatorcircuitry 318 be provided in the meter device 12 instead of, or inaddition to, being provided in the option device 16. For the embodimentin which data path 210 is parallel (e.g., includes a plurality ofparallel data paths) the conversion device 316 and the isolatorcircuitry 318 are provided with the option device 16, the data path 320is serial, and one electro-isolator is provided along data path 320,which is beneficial for minimizing costs and complexity of the meterdevice 12.

It is further contemplated that the processor 304 utilizes a parallelprotocol and transmits and receives data in parallel format. In oneembodiment, a second conversion device 316 is provided in between theprocessor 304 and the isolator circuitry 318. Accordingly, data beingexchanged with the processor 304 passes serially through the isolatorcircuitry 318. In another embodiment of the disclosure, data isexchanged in parallel (e.g., along a plurality of parallel data paths)between the meter device 12 (e.g., the processor assembly 202 and/or orother devices of the meter device 12) and the processor 304, and theconversion device 316 is omitted. Isolator circuitry 318 is provided foroperating on each path of parallel data. It is further contemplated thatthe processor assembly 202 and/or other devices of the meter device 12and the processor 304 utilize a serial protocol, and data is exchangedalong a single data path. Conversion device 316 is omitted, and theisolator circuitry 318 is provided along the single data path.

The option device components 302 include one or more digital and/oranalog devices which add functionality to the meter device 12, such asproviding for processing signals generated by the meter device 12 andgenerating output signals. The option device components 302 may includeat least one input/output (I/O) device 322, for transmitting the outputsignals via a wired or wireless communication medium using acommunication protocol, such as a serial, parallel, Ethernet, Internet,etc., protocol.

A first example of an option device 16 is a fiber optic port, preferablyfor providing serial fiber optic communication. Preferably, thecommunication protocol used is half duplex, and circuitry is providedfor allowing the option device to be used in a closed loop. The protocolis preferably user selectable during configuration, such as from ModbusRTU, Modbus ASCII, or distributed network protocol (DNP) 3.0 protocols.The address for the option device is also preferably user selectableduring configuration, such as from addresses ranging between 1 and 247.The baud rate is preferably user selectable during configuration, suchas from a speed of 9600; 19,200; 38,400; or 57,600 baud. The bytestructure is preferably user selectable during configuration, such asfrom 5, 6, 7, or 8 bits. Parity is preferably user selectable duringconfiguration, such as from even, odd or none. Stop bits are preferablyuser selectable during configuration, such as to 1 or 2. A reply delay(an intentional delay prior to responding to a data request) ispreferably user selectable during configuration, such as ranging from 0to 500 milliseconds in increments, e.g., increments of 50 milliseconds.

A second example of an option device 16 is an Ethernet card forautomatically sensing and connecting to either a network connection,such as a 10 or 100 MHz LAN connection. Preferably, the option device 16supports multiple, e.g., twelve, simultaneous socket connections.Preferably, networking features, such as the IP address, Subnet Mask,and Gateway address are user selectable during configuration. Preferablythe option device 16 supports a dynamic host configuration protocol(DHCP) connection. Additionally, the option device 16 includes astandard network connector, such as an RJ-45 jack.

A third exemplary option card 16 is a digital I/O relay option card forproviding two status inputs. Preferably, inputs are received viaseveral, e.g., three pins, including one common and two channels, whichpreferably automatically adjust to a connection with dry contacts orwetted voltage signals. The inputs are sampled at regular intervals,such as 100 millisecond intervals, and are de-bounced. Preferably, thestatus of each input is stored in readable registers that are accessiblevia another communication port, e.g., using a protocol, such as Modbusor DNP protocols. Preferably, one of the input channels is configurableto sense an end-of-interval pulse from an external energy meter.

The digital I/O relay option device preferably includes multiple, e.g.,three, relay outputs controllable through a communication port using acompatible protocol. The relays are preferably user configurable tooperate automatically in response to meter limit conditions, includingapplication of hysteresis to more than one limit. Preferably, a userselectable delay time is provided for delaying a reset procedure whenrelays are assigned to limits.

A fourth example of an option device 16 is a digital I/O energy pulsecounting option card for counting received digital pulses and convertingthe pulses into corresponding energy usage values. The digital I/Oenergy pulse counting option card preferably provides a (e.g., one)status input, e.g., through two pins, including one common and onechannel which automatically adjusts to connection to dry contacts orwetted voltage signals. Preferably, the input is sampled at regularintervals, e.g., 100 milliseconds intervals, and de-bounced. The statusof each input is preferably stored in readable registers accessible viaa communication port using a protocol, such as Modbus or DNP protocols.The inputs are preferably configured to sense an end-of-interval pulsefrom an external energy meter.

A fifth option device is an analog output option device having multiple(e.g., four) analog outputs for outputting 0-±1 mA proportional to areceived input. The channels measure a quantity which is preferablyselectable by the user from voltage, current, watt, VAR, VA orfrequency. Additionally, the magnitude of the scalar quantity thatcorresponds to 0 mA and to 1 mA for each channel is preferably userselectable during configuration, such as defined by set points, whichmay be positive or negative numbers. Each channel provides an outputthat is linear between the set points as the scalar quantity changesbetween the set points. Furthermore, each channel is preferablyconfigurable as unidirectional or bidirectional, where when the channelis configured as bidirectional, the channel produces an output from −1mA to +1 mA, and the set points are −1 and +1 mA. Preferably, the analogoutput option device is self-powered to provide 1 mA into a 10 kΩ loadfor each channel, with each channel capable of producing an output of20% over rating.

A sixth option card is an analog output option card having eight analogoutput channels connected through one common and eight channelconnections for providing an output from 0 to 20 mA. The channelsmeasure a quantity which is preferably selectable by the user fromvoltage, current, watt, VAR, VA, frequency, power factor, phase angle,harmonic magnitude and harmonic angle. Set points are preferably userselectable for specifying the magnitude of the scalar quantity thatcorresponds to 4 mA and to 20 mA for each channel. These set points maybe positive or negative numbers. Each channel preferably provides anoutput that is linear between the set points as the scalar quantitychanges between the set points. Preferably, the analog output optiondevice is self-powered to provide 20 mA into a 250 Ω load for eachchannel, with each channel capable of producing an output of 20% overrating.

Accordingly, a respective option device 16 may generate and outputanalog retransmit signals, pulse signals, digital communication signals,Ethernet signals, control signals, or other telemetric outputs, wherethe output signals are based on the measured values. The output signalsmay be transmitted to an external device (not shown), such as a server,another processing device, a cellular phone, a controllable device, etc.It is contemplated that the I/O device 322 may receive information froman external device (not shown) which the processor 304 may process,and/or provide to the meter device 12 via the interface device 314 andthe connector 214.

In a preferred embodiment in accordance with the present disclosure, theoption device 16 is installed with the meter device 12 by couplingconnectors 212 and 204 and connectors 214 and 208, which may beaccomplished, for example, by inserting the option device 16 in anoption device slot of the interface 14 of the meter device 12.Installation of the option device 16 with the meter device 12 addsfunctionality to the meter device 12. Preferably, the option devices 16and the interfaces 14 are standardized for allowing an operator toinstall a selected option device 16 with the meter device 12 for addingfunctionality to the meter device 12.

The meter device 12 recognizes the presence of the installed optiondevice 16 and is automatically configured to communicate and operatewith the option device 16 in order that the functionality of the optiondevice 16 is integrated into the functionality of the meter device 12.The meter device 12 exchanges appropriate information with the optiondevice 16, enabling the option device 16 to operate compatibly with themeter device 12 for adding functionality thereto. More specifically, theprocessor assembly of the meter device 16 exchanges signals (in at leastone direction) with the processor 304 of the option device 16, where theexchanged signals pass through an isolation barrier for protecting thehardware of both of the meter device 12 and the option device 16 and theintegrity of the exchanged signals. The exchanged information mayinclude data that relates to the energy inputs received by the meterdevice 16 and/or control signals.

The meter device 12 may be provided with a desired number of interfaces14, each available for coupling with an option device 16. When multipleoption devices 16 are coupled to the meter device 12, the functionalityof the meter device 12 may be increased to include the option functionprovided by each of the option devices 16. Prioritization data may beprovided, where needed, for determining prioritization of the addedoption functions, when one option function may override another, whichoption function may override another, etc. The prioritization data maybe provided via the meter device 12 and/or the option device 16.

Multiple option devices 16 may be packaged as a kit, where two or moreoption devices 16 may be installed with the meter device 12 at a time,and/or a first option device 16 providing a first option function of thekit may be interchanged with a second option device 16 providing asecond option function of the kit for changing the functionality of themeter device 12 from including the first option function to include thesecond option function instead of the first option function.Furthermore, the meter device 12 may be included with the kit.Additionally the option devices 16 and/or a kit of option devices 16 mayoperate with a variety of meter devices 12.

In accordance with the above disclosure, the meter device 12 may operatefor increasing functionality of the meter device 12 with any optiondevice 16 designed for compatibility with the meter device 12, such asin accordance with a standard which may specify dimensions of the optiondevice 16, the types of connectors to be used and the type of protocolto be used. A universal increase of functionality of meter devices isavailable to all meter devices and option devices which adhere to thestandards.

The described embodiments of the present disclosure are intended to beillustrative rather than restrictive, and are not intended to representevery embodiment of the present disclosure. Various modifications andvariations can be made without departing from the spirit or scope of thedisclosure as set forth in the following claims both literally and inequivalents recognized in law.

What is claimed is:
 1. A method for upgrading a power meter, the methodcomprising the steps of: providing a power meter configured to perform abase level of functionality for measuring electrical parameters relatedto an amount of power consumed at a particular location, wherein thepower meter comprises a first interface having a first connector coupledto a first data path and a second connector coupled to a second datapath, and wherein the power meter further comprises a second interfacehaving a first connector coupled to the first data path and a secondconnector coupled to the second data path; providing a plurality ofexternal option devices, wherein each external option device comprises afirst connector and a second connector, and wherein each external optiondevice is configured to enable the power meter to perform at least oneoptional function in addition to the base level of functionality;allowing a user to select a first external option device from theplurality of external option devices and couple the first externaloption device with the first interface of the power meter such that thefirst connector of the first external option device contacts the firstconnector of the first interface and the second connector of the firstexternal option device contacts the second connector of the firstinterface; sending initialization data from a storage device disposed inthe first external option device via the first connector of the firstexternal option device to the first data path of the power meter via thefirst connector of the first interface, wherein the initialization dataenables the power meter to operate with the first external optiondevice; sending electrical parameters measured by the power meter viathe second data path and second connector of the first interface to thefirst external option device via the second connector of the firstexternal option device; processing the electrical parameters by thefirst external option device; and operating the power meter with thefirst external option device, wherein the at least one optional functionis added to the base level of functionality of the power meter when thefirst external option device is coupled with the first interface of thepower meter and the power meter receives the initialization data fromthe first external option device.
 2. The method of claim 1, furthercomprising the steps of: allowing the user to uncouple the firstexternal option device from the first interface of the power meter,select a second external option device from the plurality of externaloption devices, and couple the second external option device with thefirst interface of the power meter such that the first connector of thesecond external option device contacts the first connector of the firstinterface and the second connector of the second external option devicecontacts the second connector of the first interface; sendinginitialization data from a storage device disposed in the secondexternal option device via the first connector of the second externaloption device to the first data path of the power meter via the firstconnector of the first interface, wherein the initialization dataenables the power meter to operate with the second external optiondevice; sending electrical parameters measured by the power meter viathe second data path and second connector of the first interface to thesecond external option device via the second connector of the secondexternal option device; processing the electrical parameters by thesecond external option device; and operating the power meter with thesecond external option device, wherein the at least one optionalfunction is added to the base level of functionality of the power meterwhen the second external option device is coupled with the firstinterface of the power meter and the power meter receives theinitialization data from the second external option device.
 3. Themethod of claim 1, further comprising the steps of: allowing the user toselect a second external option device from the plurality of externaloption devices and couple the second external option device with thesecond interface of the power meter such that the first connector of thesecond external option device contacts the first connector of the secondinterface and the second connector of the second external option devicecontacts the second connector of the second interface; sendinginitialization data from a storage device disposed in the secondexternal option device via the first connector of the second externaloption device to the first data path of the power meter via the firstconnector of the second interface, wherein the initialization dataenables the power meter to operate with the second external optiondevice; sending electrical parameters measured by the power meter viathe second data path and second connector of the second interface to thesecond external option device via the second connector of the secondexternal option device; processing the electrical parameters by thesecond external option device; and operating the power meter with thefirst external option device and second external option device, whereinthe at least one optional function of each of the first external optiondevice and second external option device is added to the base level offunctionality of the power meter when the first external option deviceis coupled with the first interface, when the second external optiondevice is coupled with the second interface, and the power meterreceives the initialization data from each of the first external optiondevice and second external option device.
 4. The method of claim 1,further comprising the step of operating the power meter when the firstexternal option device is uncoupled from the power meter, the powermeter configured to perform the base level of functionality whenuncoupled from the first external option device.
 5. The method of claim1, wherein the initialization data includes identification dataidentifying the first external option device, and further comprising thestep of using the identification data to configure the power meter tooperate with the first external option device to enable the power meterto perform the at least one option function in addition to the baselevel of functionality of the power meter.
 6. The method of claim 1,wherein the initialization data includes at least one gain factorcorresponding to the gain of the first external option device.
 7. Themethod of claim 1, wherein the initialization data includes executableinstructions for execution by a processor of the power meter.
 8. Themethod of claim 1, further comprising one of the steps of: convertingthe electrical parameters from a serial format to a parallel format; andconverting the electrical parameters from a parallel format to a serialformat.
 9. The method of claim 1, further comprising the step ofelectrically isolating the power meter from the first external optiondevice along the second data path.
 10. The method of claim 9, whereinthe step of electrically isolating the power meter from the firstexternal option device comprises the step of providingoptical-electrical isolator circuitry along a path established between aprocessor of the first external option device and a processor of thepower meter.
 11. The method of claim 1, wherein the steps of sendinginitialization data and sending electrical parameters includes using acommunication protocol to transmit via one of a wired communicationmedium and a wireless communication medium.
 12. The method of claim 11,wherein the communication protocol is selected from the group consistingof Modbus RTU, Modbus ASCII, DNP, serial, parallel, Ethernet, andInternet communication protocols.
 13. The method of claim 1, wherein thefirst external option device is selected from the group consisting of afiber optic port, an Ethernet card, a digital I/O card, and an analogoutput option device.
 14. A method comprising the steps of: selecting anoption device from a plurality of option devices, wherein each optiondevice includes a first connector and a second connector, wherein eachoption device is configured to provide an additional option function toexisting functionality of a meter device, wherein the meter device isconfigured to measure parameters of energy, wherein the meter devicecomprises a first option interface having a first connector coupled to afirst data path and a second connector coupled to a second data path,and wherein the meter device further comprises a second option interfacehaving a first connector coupled to the first data path and a secondconnector coupled to the second data path; coupling the selected optiondevice with the first option interface of the meter device such that thefirst connector of the selected option device contacts the firstconnector of the first option interface and the second connector of theselected o ton device contacts the second connector of the first optioninterface, wherein the respective additional option function is providedto the existing functionality of the meter device when the selectedoption device is coupled with the first option interface; electricallyisolating the meter device from the selected option device along thesecond data path of the meter device; exchanging initialization dataalong the first data path of the meter device; exchanging data relatedto the measured parameters of energy along the second data path of themeter device; and operating the meter device with the selected optiondevice, wherein the additional option function is added to the existingfunctionality of the meter device when the selected option device iscoupled with the meter device and the initialization data is exchanged;wherein the initialization data is sent from a storage device disposedin the selected option device to the meter device to be used by themeter device for configuring the meter device to be in condition tooperate with the selected option device.
 15. The method of claim 14,wherein the steps of exchanging initialization data and exchanging datarelated to the measured parameters of energy include transmitting viaone of a wired communication medium and a wireless communication medium.16. The method of claim 15, wherein transmitting via one of a wiredcommunication medium and a wireless communication medium includestransmitting under a communication protocol selected from the groupconsisting of Modbus RTU, Modbus ASCII, DNP, serial, parallel, Ethernet,and Internet communication protocols.
 17. The method of claim 14,wherein the selected option device is selected from the group consistingof a fiber optic port, an Ethernet card, a digital I/O card, and ananalog output option device.
 18. The method of claim 14, furthercomprising the steps of: uncoupling the selected option device from thefirst option interface of the meter device; selecting a second optiondevice from the plurality of option devices; and coupling the secondoption device with the first option interface of the meter device suchthat the first connector of the second option device contacts the firstconnector of the first option interface and the second connector of thesecond option device contacts the second connector of the first optioninterface.
 19. The method of claim 18, further comprising the steps of:exchanging initialization data along the first data path of the meterdevice; exchanging data related to the measured parameters of energyalong the second data path of the meter device; and operating the meterdevice with the second option device, wherein the additional optionfunction is added to the existing functionality of the meter device whenthe second option device is coupled with the meter device and theinitialization data is exchanged.
 20. The method of claim 14, furthercomprising the steps of: selecting a second option device from theplurality of option devices; and coupling the second option device withthe second option interface of the power meter such that the firstconnector of the second option device contacts the first connector ofthe second option interface and the second connector of the secondoption device contacts the second connector of the second optioninterface.
 21. The method of claim 20, further comprising the steps of:sending initialization data from a storage device disposed in the secondoption device via the first connector of the second option device to thefirst data path of the meter device via the first connector of the firstoption interface, wherein the initialization data enables the powermeter to operate with the second option device; sending data related tothe measured parameters of energy from the meter device via the seconddata path and second connector of the second option interface to thesecond option device via the second connector of the second optiondevice; and operating the meter device with the selected option deviceand second option device, wherein the additional optional function ofeach of the selected option device and second option device is providedto the existing functionality of the meter device when the selectedoption device is coupled with the first option interface, when thesecond option device is coupled with the second option interface, andthe power meter receives the initialization data from each of theselected option device and second option device.